Physical properties of equilibrium and nonequilibrium liquid osmium measured by levitation techniques.

To initiate a comprehensive study of the macroscopic and microscopic properties and structure of osmium, solid samples were levitated, melted, deeply undercooled, and resolidified under vacuum. Using noncontact diagnostic methods, several properties of equilibrium and nonequilibrium liquid osmium were measured. Over the 2670–3380 K temperature range, the density could be expressed as ρ(T)=1.91×104-1.16(T-Tm) kg m-3, where Tm is the melting temperature (Tm=3306 K). Similarly, the surface tension and the viscosity measurement data could be fitted, respectively, as σ(T)=2.48×103-0.34(T-Tm) mN m-1 and η(T)=0.001 67 exp[2.2×105/(RT)] mPa s over the 3230–3605 K temperature interval. [ABSTRACT FROM AUTHOR]